;;; flow-ctrl.el --- help for lusers on cu(1) or ttys with wired-in ^S/^Q flow control;; Copyright (C) 1990, 1991, 1994 Free Software Foundation, Inc.;; Author Kevin Gallagher;; Maintainer: FSF;; Adapted-By: ESR;; Keywords: hardware;; This file is part of GNU Emacs.;; GNU Emacs is free software; you can redistribute it and/or modify;; it under the terms of the GNU General Public License as published by;; the Free Software Foundation; either version 2, or (at your option);; any later version.;; GNU Emacs is distributed in the hope that it will be useful,;; but WITHOUT ANY WARRANTY; without even the implied warranty of;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the;; GNU General Public License for more details.;; You should have received a copy of the GNU General Public License;; along with GNU Emacs; see the file COPYING. If not, write to the;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,;; Boston, MA 02111-1307, USA.;;; Commentary:;; Terminals that use XON/XOFF flow control can cause problems with;; GNU Emacs users. This file contains Emacs Lisp code that makes it;; easy for a user to deal with this problem, when using such a;; terminal. ;; ;; To invoke these adjustments, a user need only invoke the function;; enable-flow-control-on with a list of terminal types in his/her own;; .emacs file. As arguments, give it the names of one or more terminal;; types in use by that user which require flow control adjustments.;; Here's an example: ;; ;; (enable-flow-control-on "vt200" "vt300" "vt101" "vt131");; Portability note: This uses (getenv "TERM"), and therefore probably;; won't work outside of UNIX-like environments.;;; Code:(defvarflow-control-c-s-replacement?\034"Character that replaces C-s, when flow control handling is enabled.")(defvarflow-control-c-q-replacement?\036"Character that replaces C-q, when flow control handling is enabled.")(put'keyboard-translate-table'char-table-extra-slots0);;;###autoload(defunenable-flow-control(&optionalargument)"Toggle flow control handling.When handling is enabled, user can type C-s as C-\\, and C-q as C-^.With arg, enable flow control mode if arg is positive, otherwise disable."(interactive"P")(if(ifargument;; Argument means enable if arg is positive.(<=(prefix-numeric-valueargument)0);; No arg means toggle.(nth1(current-input-mode)))(progn;; Turn flow control off, and stop exchanging chars.(set-input-modetnil(nth2(current-input-mode)))(ifkeyboard-translate-table(progn(asetkeyboard-translate-tableflow-control-c-s-replacementnil)(asetkeyboard-translate-table?\^snil)(asetkeyboard-translate-tableflow-control-c-q-replacementnil)(asetkeyboard-translate-table?\^qnil))));; Turn flow control on.;; Tell emacs to pass C-s and C-q to OS.(set-input-modenilt(nth2(current-input-mode)));; Initialize translate table, saving previous mappings, if any.(cond((nullkeyboard-translate-table)(setqkeyboard-translate-table(make-char-table'keyboard-translate-tablenil)))((char-table-pkeyboard-translate-table)(setqkeyboard-translate-table(copy-sequencekeyboard-translate-table)))(t(let((the-table(make-char-table'keyboard-translate-tablenil)))(let((i0)(j(lengthkeyboard-translate-table)))(while(<ij)(asetthe-tablei(eltkeyboard-translate-tablei))(setqi(1+i))))(setqkeyboard-translate-tablethe-table))));; Swap C-s and C-\(asetkeyboard-translate-tableflow-control-c-s-replacement?\^s)(asetkeyboard-translate-table?\^sflow-control-c-s-replacement);; Swap C-q and C-^(asetkeyboard-translate-tableflow-control-c-q-replacement?\^q)(asetkeyboard-translate-table?\^qflow-control-c-q-replacement)(message"XON/XOFF adjustment for %s: use %s for C-s, and use %s for C-q"(getenv"TERM")(single-key-descriptionflow-control-c-s-replacement)(single-key-descriptionflow-control-c-q-replacement))(sleep-for2))); Give user a chance to see message.;;;###autoload(defunenable-flow-control-on(&restlosing-terminal-types)"Enable flow control if using one of a specified set of terminal types.Use `(enable-flow-control-on \"vt100\" \"h19\")' to enable flow controlon VT-100 and H19 terminals. When flow control is enabled,you must type C-\\ to get the effect of a C-s, and type C-^to get the effect of a C-q."(let((term(getenv"TERM"))hyphend);; Look for TERM in LOSING-TERMINAL-TYPES.;; If we don't find it literally, try stripping off words;; from the end, one by one.(while(andterm(not(membertermlosing-terminal-types)));; Strip off last hyphen and what follows, then try again.(if(setqhyphend(string-match"[-_][^-_]+$"term))(setqterm(substringterm0hyphend))(setqtermnil)))(ifterm(enable-flow-control))))(provide'flow-ctrl);;; flow-ctrl.el ends here